The invention relates to a heat sink for an electric circuit board on which is mounted at least one heat-generating component which requires cooling.
One of the most frequently used methods of designing such a heat sink is to adapt the heat sink to a certain particular component, the heat sink being fixed to the actual component upon assembly. A circuit board can thus come to include a number of different heat sinks positioned in different places on the circuit board. The work of mounting these heat sinks on the respective different components is both extensive and expensive. The scattered positioning on the circuit board of the heat sinks means that special arrangements are required in order to supply cooling air to the heat sink, which in turn results in difficulties in positioning other electronic components closer to one another on the circuit board. In the event that it is desired to position a number of circuit boards close to one another, the positioning of the heat sinks prevents these circuit boards being positioned near one another.
With a view to simplifying the mounting of the heat-generating components on a heat sink, it is known through U.S. Pat. No. 4,674,005 to arrange one heat sink which is common to several components. In this connection the heat sink extends along the one edge of the circuit board and is screwed securely on its upper side. The heat-generating components are gathered along the edge of the circuit board and under the bias of a common tensioning element bear against the heat sink. Arranging a common heat sink for several components in this manner certainly leads to advantages, but also to disadvantages. The heat sink is screwed securely to a housing enclosing the circuit board for transfer of the heat to the housing. This can be simply arranged if there is only one circuit board which is to be connected to the housing in this manner. In the event that the housing is to contain a number of circuit boards, no indication is given as to how this is to be arranged.
International patent specification W086/06334 shows how a number of circuit boards are arranged in a common housing. In this case the heat sinks are designed as base plates, which extend parallel to the respective circuit boards. The base plates are at their sides connected to the housing for further transfer of the heat. However, this design requires a relatively complicated join between the base plates which serve as heat sinks and their connection in the housing. This means that this arrangement also can be considered as complicated.